A woman touches fresh eggs at a chicken farm in Gaesti, southern Romania, Friday, Aug. 11, 2017. The European Union said Friday that it plans to hold an extraordinary meeting late next month over a growing tainted egg scandal as it revealed that products contaminated with an insecticide have now spread to 17 countries.(AP Photo/Vadim Ghirda)

AMSTERDAM (AP) — Experts say the risk of getting sick from eating an egg tainted with insecticide is low. But that hasn’t stopped stores in Germany and the Netherlands from stripping them from supermarket shelves, or prevented other European food safety agencies from issuing warnings.

The story about the illegal use of the insecticide Fipronil in spray to rid hens of ticks, fleas and lice has gained traction across Europe. Fears about the safety of an everyday food staple along with some less-than-optimal public information have combined to cast a shadow of suspicion over the humble egg.

“I take it seriously,” she said of the Dutch warning. “I’m not scared that I’ll collapse if I eat the wrong egg, but if you can prevent something …”

Fipronil is commonly used by veterinarians to treat fleas and ticks in pets, but is banned by the European Union for treating animals like chickens that are part of the human food chain.

The EU said contaminated eggs have been found at producers in Belgium, France, Germany and the Netherlands. It’s believed the Fipronil got into the food chain when it was illegally added to a product used to spray poultry.

The impact for egg producers has been staggering.

Since July 20, Dutch farmers have destroyed millions of unsellable eggs and culled about 1 million hens, said Hennie de Haan of the Dutch union of poultry farmers.

But nobody has been reported to have fallen ill as a result of eating the tainted eggs.

“People are very susceptible to negative information,” said Jan-Willem van Prooijen, a social psychologist at the Vrije Universiteit Amsterdam. “People are very attuned to perceive and respond emotionally to negative information such as potential health hazards or other threatening stimuli.”

In recent days, Dutch authorities blocked sales from about 180 infected farms treated by a company suspected of illicitly using Fipronil.

Almost all lab tests show that only very low levels of Fipronil — seven to 10 times lower than the maximum permitted — have been detected in eggs from the treated chickens, although one test in Belgium was above the European limit. Poisoning by small doses has few effects and requires little treatment. Heavy and prolonged exposure can damage the kidneys and liver or cause seizures.

Dutch authorities warned that eggs from only one farm should not be eaten and said children should not eat eggs from dozens of other farms.

That sent consumers to their refrigerators to check the small codes printed in red ink on the shells of eggs to see if they are from one of the affected farms. Stores have pulled eggs from contaminated farms off their shelves.

The European Union said Friday that tainted eggs have been found so far in 15 EU countries, plus Switzerland and Hong Kong.

In Germany, some supermarkets stopped selling all Dutch eggs regardless of whether they came from infected farms. British authorities issued a warning about a small number of ready-made salads, sandwiches and spreads containing contaminated eggs.

The precautions came despite food safety experts being nearly unanimous in their opinion that the health risk from eating Fipronil-tainted eggs is very low.

“Even when taken deliberately at 10,000 times the maximum amount likely to be consumed from contaminated eggs, the individuals survived with no long-term harm,” Alan Boobis, professor of biochemical pharmacology, Imperial College London, said in a statement.

“Based on the extent of contamination found and the number of such eggs that have reached the U.K. market, there is no reason for consumers to be concerned,” he added.

So why are consumers concerned?

“Bad is stronger than good,” said Van Prooijen, citing a time-honored maxim among psychologists. “And that means human beings pay more attention to negative things than positive things, because negative things can harm you.”

Some farmers say the Netherlands’ food safety watchdog last week fanned such fears.

The acting inspector-general of the Netherlands Food and Consumer Product Safety Authority, Freek van Zoeren, said on a Dutch TV news show that, “if somebody says ‘I can live without eggs until Sunday,’ I’d advise that.”

Dutch Health Minister Edith Schippers acknowledged on another show Thursday night that the statement was ill-judged.

Anja Visscher, whose 110,000 white hens lay about 100,000 eggs each day, quickly took to Facebook and the internet to reassure customers after Van Zoeren’s comment.

“There are companies whose eggs are OK, so eat an egg,” was the message she and other farmers spread. “You want the market to remain OK.”

On Thursday, authorities arrested two men in the Netherlands who were directors of the company involved in spraying poultry barns, saying they endangered public health. Their identities have not been released while a criminal investigation continues.

Farmers have said they were unaware the spray contained Fipronil and see themselves as unwitting victims. In the Netherlands, they also blame the food safety watchdog for not acting fast enough after receiving an anonymous tip about possible Fipronil use in November 2016.

Some industry groups say the scandal should be a wake-up call.

“Citizens want something cleaner, better, and we have been working on that,” said Philippe Duvivier, president of FUGEA, a Belgian farmers’ group working for sustainable agriculture. “We have to call the whole sector into question now. Perhaps it’s time to go to a whole other kind of agriculture.”